>Could someone explain why this is cool, when whilst other companies face anti-trust cases for including things like a browser or media player?
Sure. First it's other company (singular) not companies. That other company was Microsoft. In the 2000s they were deemed a monopoly and judged as leveraging their monopoly power to stifle competition (Netscape) by packaging a browser in their OS for free thus effectively cutting off Netscape's income (who charged for their browser).
Apple is not a monopoly. Not even close. They are vertically integrated, meaning they make many of the parts from hardware to software, to chips themselves. Other companies outsource to other companies, they are horizontally integrated. They make and specialize in mostly 1 layer (OS or hardware, or parts, etc).
Back in the day, all personal computer manufacturers (Commodore, Atari, Coleco, Apple, etc) were vertically integrated until IBM was caught with their pants down, and threw together what we now know as a PC using parts from other vendors. IBM just made the BIOS and bought the rest of the parts from other companies. During the dawn of the computer revolution, it worked well, but in my opinion it stifled innovation at least at the software level. Once Microsoft knocked off Novell (it's last OS victim) it really had no motivation to be creative (or no one to steal from). Thus, Windows 98, ME, XP, Vista. (Yes XP was great but no great leap from 2K).
The point of all that is that Apple is finally returning innovation to the personal computer realm, and I whole heartedly welcome it. They are able to do things most horizontal companies can't (even if they wanted to which they didn't until Apple) because they are more vertical. The PC industry has been stagnant for the past decade due to the big fish raking in the cash simply because they dominated the market, mainly by having the most installs. If Apple takes the market, they may do the same, but it will be a long time until they do.